In scenes on the US TV show that are yet to air in the UK, Matthew's character Will Schuester gets close to Gwyneth's character Holly Holliday.
But it proved to be a bit of a traumatic experience for the 32-year-old.
He told British Independent newspaper: 'I was actually sick when we were filming it, and we were trying to think of different ways to do it without kissing.'
But Paltrow, 38, didn't let a bit of sick get to her.
Matthew added: 'She's like, 'Come on, let's go for it.' I was like, 'All right... like your dedication to the work, Gwyneth.''